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09:58
Investigating the Three-dimensional Flow Separation Induced by a Model Vocal Fold Polyp
Published on: February 3, 2014
Separation of a binary fluid mixture in a porous horizontal cavity
Bilal Elhajjar1, Marie-Catherine Charrier-Mojtabi, Abdelkader Mojtabi
1IMFT, UMR CNRS/INP/UPS No 5502, UFR MIG, Université Paul Sabatier, 118 Route de Narbonne, 31062, Toulouse Cedex, France.
Summary
This study demonstrates thermogravitational separation in horizontal Rayleigh-Bénard cells, achieving efficient species separation without remixing issues common in vertical thermogravitational columns (TGCs). Optimal separation is possible before flow instability, offering a more efficient industrial process.
Area of Science:
- Fluid dynamics
- Thermodynamics
- Separation science
Background:
- Thermogravitational separation traditionally uses vertical thermogravitational columns (TGCs).
- Vertical TGCs face remixing issues with fluids having negative Soret coefficients, leading to instability.
- Existing methods lack efficiency for industrial-scale separation processes.
Purpose of the Study:
- To investigate thermogravitational species separation in a horizontal Rayleigh-Bénard configuration.
- To determine if stable monocellular flow can be maintained for optimal separation.
- To compare separation efficiency with traditional vertical TGCs.
Main Methods:
- Analysis of binary fluid mixture separation in a horizontal porous layer under Soret effect.
- Study of stability loss via stationary and Hopf bifurcations based on separation ratio (psi).
- Investigation of monocellular flow stability and its relation to optimal separation conditions.
Main Results:
- Species separation achieved in a horizontal cell without remixing, even with negative Soret coefficients.
- Monocellular flow established for specific separation ratios (psi > psi(mono) > 0).
- Optimal separation achieved before the loss of monocellular flow stability.
- Horizontal configuration yields comparable separation degree with greater species quantity than vertical TGCs.
Conclusions:
- Horizontal Rayleigh-Bénard cells offer a viable and efficient alternative for thermogravitational separation.
- The method overcomes remixing limitations of vertical TGCs, enhancing industrial process potential.
- This configuration allows for controlled separation and improved yield compared to conventional methods.
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